The present invention relates in general to methods and apparatus for removing excess moisture from air streams and in particular to a method and apparatus that removes excess moisture from compressed air streams through a unique cooling and condensation process.
Compressed air systems are utilized in a wide variety of applications and industries ranging from repair shops, construction sites, manufacturing, and dry cleaning facilities to home use. In areas where relative humidity is high, water build up in air lines can cause severe problems. Water in the air lines can shorten the life of air tools, clump media in sandblasting operations, ruin delicate parts during air jet cleaning processes, damage air driven components within machinery or produce inferior painted surfaces. Excessive water and water buildup in the air storage tanks corrodes and damages tanks prematurely.
There are a number of methods and devices on the market intended to remove free moisture from compressed air streams. There are two primary types of prior art dryers, refrigerant and media dryers. Refrigerant dryers commonly utilize are refrigerant such as fluorocarbons that are expensive and detrimental to the environment. Media type dryers typically include desiccants which must be replaced or regenerated periodically. The bulk of these prior art devices are very expensive, large, exhibit environmental concerns, and are maintenance intensive and operationally sensitive.
It would be a benefit therefore to have a method and apparatus which removes excess water from an air stream and that is easily installable in an air system. It would be a still further benefit to have a method and apparatus for removing excess moisture from an air stream that utilizes material which is readably available and environmentally safe. It would be a still further benefit to have a method and apparatus for removing excess moisture from an air stream that is inexpensive and relatively maintenance free.
Accordingly, a method and apparatus for reducing the moisture content of a gas stream is provided. The apparatus includes a shell having a least one tube disposed therein and a condensate trap attached to the shell. A gas stream inlet and outlet are provided so that the gas stream may flow through tubes or shell, and preferably through the tubes although it is contemplated to flow the gas stream through the shell side. The drying apparatus further includes a coolant and/or volatile fluid inlet and outlet to flow a fluid such as, but not limited to, water, alcohol, or acetone to cool the gas stream and condense moisture contained therein. The drying apparatus and method of the present invention may further include a vaporization unit for vaporizing the volatile fluid with a stream of gas such as air to form a cool vapor cloud to pass through the drying apparatus.
An apparatus for reducing the moisture content of a gas stream is provided that includes a shell and tube exchanger having a gas inlet and gas outlet, a coolant inlet and coolant outlet, a condensate trap, and a condensate drain, wherein the gas inlet is connectable within a gas stream whereby the gas stream is routed through the inlet, the tubes and discharged through the gas outlet; and a coolant transmitted through the coolant inlet, through the shell, and by the tubes and discharged through the coolant outlet. The coolant may be any type fluid and may be water which is available and most sites and may be a vapor. The gas stream may be formed of substantially any gas including air.
The drying apparatus may include a vaporization forming a mixing nozzle and connected to the coolant inlet. A source of coolant or volatile fluid such as, but not limited to, water, alcohol, or acetone connected to the fluid inlet in communication with the mixing nozzle, and a source of charged air passing through an air nozzle in connection with the mixing nozzle of the vaporization unit to form a cool vapor within the drying unit when the volatile fluid flash vaporizes. Additionally, micro-droplets may be formed in the vapor to aid in thermal coupling with the tubes to condense the moisture in the gas stream.
The foregoing has outlined the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.